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git/setup.c

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#include "cache.h"
#include "dir.h"
#include "string-list.h"
static int inside_git_dir = -1;
static int inside_work_tree = -1;
/*
* Normalize "path", prepending the "prefix" for relative paths. If
* remaining_prefix is not NULL, return the actual prefix still
* remains in the path. For example, prefix = sub1/sub2/ and path is
*
* foo -> sub1/sub2/foo (full prefix)
* ../foo -> sub1/foo (remaining prefix is sub1/)
* ../../bar -> bar (no remaining prefix)
* ../../sub1/sub2/foo -> sub1/sub2/foo (but no remaining prefix)
* `pwd`/../bar -> sub1/bar (no remaining prefix)
*/
char *prefix_path_gently(const char *prefix, int len,
int *remaining_prefix, const char *path)
{
const char *orig = path;
char *sanitized;
if (is_absolute_path(orig)) {
const char *temp = real_path(path);
sanitized = xmalloc(len + strlen(temp) + 1);
strcpy(sanitized, temp);
if (remaining_prefix)
*remaining_prefix = 0;
} else {
sanitized = xmalloc(len + strlen(path) + 1);
if (len)
memcpy(sanitized, prefix, len);
strcpy(sanitized + len, path);
if (remaining_prefix)
*remaining_prefix = len;
}
if (normalize_path_copy_len(sanitized, sanitized, remaining_prefix))
goto error_out;
if (is_absolute_path(orig)) {
size_t root_len, len, total;
const char *work_tree = get_git_work_tree();
if (!work_tree)
goto error_out;
len = strlen(work_tree);
root_len = offset_1st_component(work_tree);
total = strlen(sanitized) + 1;
if (strncmp(sanitized, work_tree, len) ||
(len > root_len && sanitized[len] != '\0' && sanitized[len] != '/')) {
error_out:
free(sanitized);
return NULL;
}
if (sanitized[len] == '/')
len++;
memmove(sanitized, sanitized + len, total - len);
}
return sanitized;
}
char *prefix_path(const char *prefix, int len, const char *path)
{
char *r = prefix_path_gently(prefix, len, NULL, path);
if (!r)
die("'%s' is outside repository", path);
return r;
}
int path_inside_repo(const char *prefix, const char *path)
{
int len = prefix ? strlen(prefix) : 0;
char *r = prefix_path_gently(prefix, len, NULL, path);
if (r) {
free(r);
return 1;
}
return 0;
}
int check_filename(const char *prefix, const char *arg)
{
const char *name;
struct stat st;
if (!prefixcmp(arg, ":/")) {
if (arg[2] == '\0') /* ":/" is root dir, always exists */
return 1;
name = arg + 2;
} else if (prefix)
name = prefix_filename(prefix, strlen(prefix), arg);
else
name = arg;
if (!lstat(name, &st))
return 1; /* file exists */
if (errno == ENOENT || errno == ENOTDIR)
return 0; /* file does not exist */
die_errno("failed to stat '%s'", arg);
}
static void NORETURN die_verify_filename(const char *prefix,
const char *arg,
int diagnose_misspelt_rev)
{
if (!diagnose_misspelt_rev)
die("%s: no such path in the working tree.\n"
"Use 'git <command> -- <path>...' to specify paths that do not exist locally.",
arg);
/*
* Saying "'(icase)foo' does not exist in the index" when the
* user gave us ":(icase)foo" is just stupid. A magic pathspec
* begins with a colon and is followed by a non-alnum; do not
* let maybe_die_on_misspelt_object_name() even trigger.
*/
if (!(arg[0] == ':' && !isalnum(arg[1])))
maybe_die_on_misspelt_object_name(arg, prefix);
/* ... or fall back the most general message. */
die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
"Use '--' to separate paths from revisions, like this:\n"
"'git <command> [<revision>...] -- [<file>...]'", arg);
}
/*
* Verify a filename that we got as an argument for a pathspec
* entry. Note that a filename that begins with "-" never verifies
* as true, because even if such a filename were to exist, we want
* it to be preceded by the "--" marker (or we want the user to
* use a format like "./-filename")
*
* The "diagnose_misspelt_rev" is used to provide a user-friendly
* diagnosis when dying upon finding that "name" is not a pathname.
* If set to 1, the diagnosis will try to diagnose "name" as an
* invalid object name (e.g. HEAD:foo). If set to 0, the diagnosis
* will only complain about an inexisting file.
*
* This function is typically called to check that a "file or rev"
* argument is unambiguous. In this case, the caller will want
* diagnose_misspelt_rev == 1 when verifying the first non-rev
* argument (which could have been a revision), and
* diagnose_misspelt_rev == 0 for the next ones (because we already
* saw a filename, there's not ambiguity anymore).
*/
void verify_filename(const char *prefix,
const char *arg,
int diagnose_misspelt_rev)
{
if (*arg == '-')
die("bad flag '%s' used after filename", arg);
if (check_filename(prefix, arg))
return;
die_verify_filename(prefix, arg, diagnose_misspelt_rev);
}
/*
* Opposite of the above: the command line did not have -- marker
* and we parsed the arg as a refname. It should not be interpretable
* as a filename.
*/
void verify_non_filename(const char *prefix, const char *arg)
{
if (!is_inside_work_tree() || is_inside_git_dir())
return;
if (*arg == '-')
return; /* flag */
if (!check_filename(prefix, arg))
return;
die("ambiguous argument '%s': both revision and filename\n"
"Use '--' to separate paths from revisions, like this:\n"
"'git <command> [<revision>...] -- [<file>...]'", arg);
}
/*
* Test if it looks like we're at a git directory.
* We want to see:
*
* - either an objects/ directory _or_ the proper
* GIT_OBJECT_DIRECTORY environment variable
* - a refs/ directory
* - either a HEAD symlink or a HEAD file that is formatted as
* a proper "ref:", or a regular file HEAD that has a properly
* formatted sha1 object name.
*/
int is_git_directory(const char *suspect)
{
char path[PATH_MAX];
size_t len = strlen(suspect);
if (PATH_MAX <= len + strlen("/objects"))
die("Too long path: %.*s", 60, suspect);
strcpy(path, suspect);
if (getenv(DB_ENVIRONMENT)) {
if (access(getenv(DB_ENVIRONMENT), X_OK))
return 0;
}
else {
strcpy(path + len, "/objects");
if (access(path, X_OK))
return 0;
}
strcpy(path + len, "/refs");
if (access(path, X_OK))
return 0;
strcpy(path + len, "/HEAD");
if (validate_headref(path))
return 0;
return 1;
}
int is_inside_git_dir(void)
{
if (inside_git_dir < 0)
inside_git_dir = is_inside_dir(get_git_dir());
return inside_git_dir;
}
int is_inside_work_tree(void)
{
if (inside_work_tree < 0)
inside_work_tree = is_inside_dir(get_git_work_tree());
return inside_work_tree;
}
void setup_work_tree(void)
{
const char *work_tree, *git_dir;
static int initialized = 0;
if (initialized)
return;
work_tree = get_git_work_tree();
git_dir = get_git_dir();
if (!is_absolute_path(git_dir))
git_dir = real_path(get_git_dir());
if (!work_tree || chdir(work_tree))
die("This operation must be run in a work tree");
/*
* Make sure subsequent git processes find correct worktree
* if $GIT_WORK_TREE is set relative
*/
if (getenv(GIT_WORK_TREE_ENVIRONMENT))
setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
set_git_dir(remove_leading_path(git_dir, work_tree));
initialized = 1;
}
static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
{
char repo_config[PATH_MAX+1];
/*
* git_config() can't be used here because it calls git_pathdup()
* to get $GIT_CONFIG/config. That call will make setup_git_env()
* set git_dir to ".git".
*
* We are in gitdir setup, no git dir has been found useable yet.
* Use a gentler version of git_config() to check if this repo
* is a good one.
*/
snprintf(repo_config, PATH_MAX, "%s/config", gitdir);
git_config_early(check_repository_format_version, NULL, repo_config);
if (GIT_REPO_VERSION < repository_format_version) {
if (!nongit_ok)
die ("Expected git repo version <= %d, found %d",
GIT_REPO_VERSION, repository_format_version);
warning("Expected git repo version <= %d, found %d",
GIT_REPO_VERSION, repository_format_version);
warning("Please upgrade Git");
*nongit_ok = -1;
return -1;
}
return 0;
}
/*
* Try to read the location of the git directory from the .git file,
* return path to git directory if found.
*/
const char *read_gitfile(const char *path)
{
char *buf;
char *dir;
const char *slash;
struct stat st;
int fd;
ssize_t len;
if (stat(path, &st))
return NULL;
if (!S_ISREG(st.st_mode))
return NULL;
fd = open(path, O_RDONLY);
if (fd < 0)
die_errno("Error opening '%s'", path);
buf = xmalloc(st.st_size + 1);
len = read_in_full(fd, buf, st.st_size);
close(fd);
if (len != st.st_size)
die("Error reading %s", path);
buf[len] = '\0';
if (prefixcmp(buf, "gitdir: "))
die("Invalid gitfile format: %s", path);
while (buf[len - 1] == '\n' || buf[len - 1] == '\r')
len--;
if (len < 9)
die("No path in gitfile: %s", path);
buf[len] = '\0';
dir = buf + 8;
if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
size_t pathlen = slash+1 - path;
size_t dirlen = pathlen + len - 8;
dir = xmalloc(dirlen + 1);
strncpy(dir, path, pathlen);
strncpy(dir + pathlen, buf + 8, len - 8);
dir[dirlen] = '\0';
free(buf);
buf = dir;
}
if (!is_git_directory(dir))
die("Not a git repository: %s", dir);
path = real_path(dir);
free(buf);
return path;
}
static const char *setup_explicit_git_dir(const char *gitdirenv,
char *cwd, int len,
int *nongit_ok)
{
const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
const char *worktree;
char *gitfile;
int offset;
if (PATH_MAX - 40 < strlen(gitdirenv))
die("'$%s' too big", GIT_DIR_ENVIRONMENT);
gitfile = (char*)read_gitfile(gitdirenv);
if (gitfile) {
gitfile = xstrdup(gitfile);
gitdirenv = gitfile;
}
if (!is_git_directory(gitdirenv)) {
if (nongit_ok) {
*nongit_ok = 1;
free(gitfile);
return NULL;
}
die("Not a git repository: '%s'", gitdirenv);
}
if (check_repository_format_gently(gitdirenv, nongit_ok)) {
free(gitfile);
return NULL;
}
/* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
if (work_tree_env)
set_git_work_tree(work_tree_env);
else if (is_bare_repository_cfg > 0) {
if (git_work_tree_cfg) /* #22.2, #30 */
die("core.bare and core.worktree do not make sense");
/* #18, #26 */
set_git_dir(gitdirenv);
free(gitfile);
return NULL;
}
else if (git_work_tree_cfg) { /* #6, #14 */
if (is_absolute_path(git_work_tree_cfg))
set_git_work_tree(git_work_tree_cfg);
else {
char core_worktree[PATH_MAX];
if (chdir(gitdirenv))
die_errno("Could not chdir to '%s'", gitdirenv);
if (chdir(git_work_tree_cfg))
die_errno("Could not chdir to '%s'", git_work_tree_cfg);
if (!getcwd(core_worktree, PATH_MAX))
die_errno("Could not get directory '%s'", git_work_tree_cfg);
if (chdir(cwd))
die_errno("Could not come back to cwd");
set_git_work_tree(core_worktree);
}
}
else if (!git_env_bool(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, 1)) {
/* #16d */
set_git_dir(gitdirenv);
free(gitfile);
return NULL;
}
else /* #2, #10 */
set_git_work_tree(".");
/* set_git_work_tree() must have been called by now */
worktree = get_git_work_tree();
/* both get_git_work_tree() and cwd are already normalized */
if (!strcmp(cwd, worktree)) { /* cwd == worktree */
set_git_dir(gitdirenv);
free(gitfile);
return NULL;
}
offset = dir_inside_of(cwd, worktree);
if (offset >= 0) { /* cwd inside worktree? */
set_git_dir(real_path(gitdirenv));
if (chdir(worktree))
die_errno("Could not chdir to '%s'", worktree);
cwd[len++] = '/';
cwd[len] = '\0';
free(gitfile);
return cwd + offset;
}
/* cwd outside worktree */
set_git_dir(gitdirenv);
free(gitfile);
return NULL;
}
static const char *setup_discovered_git_dir(const char *gitdir,
char *cwd, int offset, int len,
int *nongit_ok)
{
if (check_repository_format_gently(gitdir, nongit_ok))
return NULL;
/* --work-tree is set without --git-dir; use discovered one */
if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
if (offset != len && !is_absolute_path(gitdir))
gitdir = xstrdup(real_path(gitdir));
if (chdir(cwd))
die_errno("Could not come back to cwd");
return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
}
/* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
if (is_bare_repository_cfg > 0) {
set_git_dir(offset == len ? gitdir : real_path(gitdir));
if (chdir(cwd))
die_errno("Could not come back to cwd");
return NULL;
}
/* #0, #1, #5, #8, #9, #12, #13 */
set_git_work_tree(".");
if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
set_git_dir(gitdir);
inside_git_dir = 0;
inside_work_tree = 1;
if (offset == len)
return NULL;
/* Make "offset" point to past the '/', and add a '/' at the end */
offset++;
cwd[len++] = '/';
cwd[len] = 0;
return cwd + offset;
}
/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
static const char *setup_bare_git_dir(char *cwd, int offset, int len, int *nongit_ok)
{
int root_len;
if (check_repository_format_gently(".", nongit_ok))
return NULL;
setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
/* --work-tree is set without --git-dir; use discovered one */
if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) {
const char *gitdir;
gitdir = offset == len ? "." : xmemdupz(cwd, offset);
if (chdir(cwd))
die_errno("Could not come back to cwd");
return setup_explicit_git_dir(gitdir, cwd, len, nongit_ok);
}
inside_git_dir = 1;
inside_work_tree = 0;
if (offset != len) {
if (chdir(cwd))
die_errno("Cannot come back to cwd");
root_len = offset_1st_component(cwd);
cwd[offset > root_len ? offset : root_len] = '\0';
set_git_dir(cwd);
}
else
set_git_dir(".");
return NULL;
}
static const char *setup_nongit(const char *cwd, int *nongit_ok)
{
if (!nongit_ok)
die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
if (chdir(cwd))
die_errno("Cannot come back to cwd");
*nongit_ok = 1;
return NULL;
}
static dev_t get_device_or_die(const char *path, const char *prefix, int prefix_len)
{
struct stat buf;
if (stat(path, &buf)) {
die_errno("failed to stat '%*s%s%s'",
prefix_len,
prefix ? prefix : "",
prefix ? "/" : "", path);
}
return buf.st_dev;
}
/*
* A "string_list_each_func_t" function that canonicalizes an entry
* from GIT_CEILING_DIRECTORIES using real_path_if_valid(), or
* discards it if unusable. The presence of an empty entry in
* GIT_CEILING_DIRECTORIES turns off canonicalization for all
* subsequent entries.
*/
static int canonicalize_ceiling_entry(struct string_list_item *item,
void *cb_data)
{
int *empty_entry_found = cb_data;
char *ceil = item->string;
if (!*ceil) {
*empty_entry_found = 1;
return 0;
} else if (!is_absolute_path(ceil)) {
return 0;
} else if (*empty_entry_found) {
/* Keep entry but do not canonicalize it */
return 1;
} else {
const char *real_path = real_path_if_valid(ceil);
if (!real_path)
return 0;
free(item->string);
item->string = xstrdup(real_path);
return 1;
}
}
/*
* We cannot decide in this function whether we are in the work tree or
* not, since the config can only be read _after_ this function was called.
*/
static const char *setup_git_directory_gently_1(int *nongit_ok)
{
const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
struct string_list ceiling_dirs = STRING_LIST_INIT_DUP;
static char cwd[PATH_MAX + 1];
const char *gitdirenv, *ret;
char *gitfile;
int len, offset, offset_parent, ceil_offset = -1;
dev_t current_device = 0;
int one_filesystem = 1;
/*
* Let's assume that we are in a git repository.
* If it turns out later that we are somewhere else, the value will be
* updated accordingly.
*/
if (nongit_ok)
*nongit_ok = 0;
if (!getcwd(cwd, sizeof(cwd) - 1))
die_errno("Unable to read current working directory");
offset = len = strlen(cwd);
/*
* If GIT_DIR is set explicitly, we're not going
* to do any discovery, but we still do repository
* validation.
*/
gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
if (gitdirenv)
return setup_explicit_git_dir(gitdirenv, cwd, len, nongit_ok);
if (env_ceiling_dirs) {
int empty_entry_found = 0;
string_list_split(&ceiling_dirs, env_ceiling_dirs, PATH_SEP, -1);
filter_string_list(&ceiling_dirs, 0,
canonicalize_ceiling_entry, &empty_entry_found);
ceil_offset = longest_ancestor_length(cwd, &ceiling_dirs);
string_list_clear(&ceiling_dirs, 0);
}
if (ceil_offset < 0 && has_dos_drive_prefix(cwd))
ceil_offset = 1;
/*
* Test in the following order (relative to the cwd):
* - .git (file containing "gitdir: <path>")
* - .git/
* - ./ (bare)
* - ../.git
* - ../.git/
* - ../ (bare)
* - ../../.git/
* etc.
*/
one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
if (one_filesystem)
current_device = get_device_or_die(".", NULL, 0);
for (;;) {
gitfile = (char*)read_gitfile(DEFAULT_GIT_DIR_ENVIRONMENT);
if (gitfile)
gitdirenv = gitfile = xstrdup(gitfile);
else {
if (is_git_directory(DEFAULT_GIT_DIR_ENVIRONMENT))
gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
}
if (gitdirenv) {
ret = setup_discovered_git_dir(gitdirenv,
cwd, offset, len,
nongit_ok);
free(gitfile);
return ret;
}
free(gitfile);
if (is_git_directory("."))
return setup_bare_git_dir(cwd, offset, len, nongit_ok);
offset_parent = offset;
while (--offset_parent > ceil_offset && cwd[offset_parent] != '/');
if (offset_parent <= ceil_offset)
return setup_nongit(cwd, nongit_ok);
if (one_filesystem) {
dev_t parent_device = get_device_or_die("..", cwd, offset);
if (parent_device != current_device) {
if (nongit_ok) {
if (chdir(cwd))
die_errno("Cannot come back to cwd");
*nongit_ok = 1;
return NULL;
}
cwd[offset] = '\0';
die("Not a git repository (or any parent up to mount point %s)\n"
"Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set).", cwd);
}
}
if (chdir("..")) {
cwd[offset] = '\0';
die_errno("Cannot change to '%s/..'", cwd);
}
offset = offset_parent;
}
}
const char *setup_git_directory_gently(int *nongit_ok)
{
const char *prefix;
prefix = setup_git_directory_gently_1(nongit_ok);
if (prefix)
setenv(GIT_PREFIX_ENVIRONMENT, prefix, 1);
else
setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
if (startup_info) {
startup_info->have_repository = !nongit_ok || !*nongit_ok;
startup_info->prefix = prefix;
}
return prefix;
}
int git_config_perm(const char *var, const char *value)
{
int i;
char *endptr;
if (value == NULL)
return PERM_GROUP;
if (!strcmp(value, "umask"))
return PERM_UMASK;
if (!strcmp(value, "group"))
return PERM_GROUP;
if (!strcmp(value, "all") ||
!strcmp(value, "world") ||
!strcmp(value, "everybody"))
return PERM_EVERYBODY;
/* Parse octal numbers */
i = strtol(value, &endptr, 8);
/* If not an octal number, maybe true/false? */
if (*endptr != 0)
return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
/*
* Treat values 0, 1 and 2 as compatibility cases, otherwise it is
* a chmod value to restrict to.
*/
switch (i) {
case PERM_UMASK: /* 0 */
return PERM_UMASK;
case OLD_PERM_GROUP: /* 1 */
return PERM_GROUP;
case OLD_PERM_EVERYBODY: /* 2 */
return PERM_EVERYBODY;
}
/* A filemode value was given: 0xxx */
if ((i & 0600) != 0600)
die("Problem with core.sharedRepository filemode value "
"(0%.3o).\nThe owner of files must always have "
"read and write permissions.", i);
/*
* Mask filemode value. Others can not get write permission.
* x flags for directories are handled separately.
*/
return -(i & 0666);
}
int check_repository_format_version(const char *var, const char *value, void *cb)
{
if (strcmp(var, "core.repositoryformatversion") == 0)
repository_format_version = git_config_int(var, value);
else if (strcmp(var, "core.sharedrepository") == 0)
shared_repository = git_config_perm(var, value);
else if (strcmp(var, "core.bare") == 0) {
is_bare_repository_cfg = git_config_bool(var, value);
if (is_bare_repository_cfg == 1)
inside_work_tree = -1;
} else if (strcmp(var, "core.worktree") == 0) {
if (!value)
return config_error_nonbool(var);
free(git_work_tree_cfg);
git_work_tree_cfg = xstrdup(value);
inside_work_tree = -1;
}
return 0;
}
int check_repository_format(void)
{
return check_repository_format_gently(get_git_dir(), NULL);
}
/*
* Returns the "prefix", a path to the current working directory
* relative to the work tree root, or NULL, if the current working
* directory is not a strict subdirectory of the work tree root. The
* prefix always ends with a '/' character.
*/
const char *setup_git_directory(void)
{
return setup_git_directory_gently(NULL);
}
const char *resolve_gitdir(const char *suspect)
{
if (is_git_directory(suspect))
return suspect;
return read_gitfile(suspect);
}
/* if any standard file descriptor is missing open it to /dev/null */
void sanitize_stdfds(void)
{
int fd = open("/dev/null", O_RDWR, 0);
while (fd != -1 && fd < 2)
fd = dup(fd);
if (fd == -1)
die_errno("open /dev/null or dup failed");
if (fd > 2)
close(fd);
}
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